1. Technical Field
The present invention relates in general to an improved composite pipe, and in particular to an improved communications mechanism for interconnecting composite pipes with metal end portions.
2. Description of the Prior Art
The use of composite materials in place of metal for various structures is desirable for many reasons, including weight reduction, corrosion resistance, durability, and increased strength. One type of structure that is useful in a variety of applications is a tube or cylinder. However, the tube must be joined to a structure of a dissimilar material at both of its axial ends to complete the terminations. Typically, a metallic end piece is used for this purpose, and may be joined to the composite via fasteners, adhesives, by the nature of end piece geometry, etc.
In some applications, such as riser pipes for downhole operations, it is desirable to transmit data from tooling located at the lower end of a string of such pipes. However, due to the extreme operating conditions in such applications, it can be difficult to maintain undistorted signals from the bottom of a well to the surface of the well. In particular, transmission of data signals must be effected throughout the length of the string of conduit and especially at the interfaces between the various sections of pipe. Thus, an improved apparatus and method of transmitting data signals in a string of pipe is needed.
One embodiment of a section of pipe for well operations has a cylindrical fiber composite pipe body and a pair of end fittings. The end fittings differ from each other in that they are provided with mating key features to ensure proper angular or rotational alignment between two abutting sections of pipe. Each pipe is also provided with an optical fiber for data transmission. The optical fiber extends along the entire length of pipe and through each end fitting. A fiber optic coupling is located at each end of the optical fiber for sending and receiving data transmissions via optical signals.
Multiple strings of pipe are abutted end to end to complete both mechanical and data interfaces. At the junction of each pair of adjacent pipes, the end fittings axially and rotationally align. The flanges of the end fittings are fastened together with bolts such that data transmission takes place between the optical fibers while a watertight mechanical seal is effected between the end fittings. Numerous strings of pipe are strung together for well operations, such as riser pipe applications, to effect both mechanical and data interfaces at each of the respective pipe junctions.
The foregoing and other objects and advantages of the present invention will be apparent to those skilled in the art, in view of the following detailed description of the preferred embodiment of the present invention, taken in conjunction with the appended claims and the accompanying drawings.